There are several synonyms for the phrase "the whole time," which refers to a continuous duration without interruption. You can use "all along," "consistently," "continuously," "endlessly," or "unceasingly" to convey the same meaning. Alternatively, you can use "always," "ever," "perpetually," or "eternally" to emphasize that the duration is continual, without any breaks or gaps. "Through and through" or "from start to finish" can also be used to express a sense of completeness or thoroughness. Whatever phrase you choose, make sure it effectively conveys the uninterrupted nature of the duration.